A pyroelectric camera is basically a television camera that is capable of producing an infrared television picture. A conventional vidicon tube may be utilized as the input of a conventional television camera to sense the target "picture" and provides an electrical signal output indicative thereof. Likewise, a pyroelectric vidicon tube may be utilized as the input of the pyroelectric camera to sense a thermal image of the target by receiving thermal energy emitted by the target and provides an electrical signal output indicative thereof. While the electron optic of a pyroelectric vidicon tube may be similar to that of a conventional vidicon tube, and while the pyroelectric vidicon tube can be focussed magnetically and/or electrostatically in the same manner as a conventional vidicon tube, the drive requirements of the pyroelectric vidicon tube differ from those of the conventional vidicon tube due, at least in part, to a necessity in the pyroelectric vidicon tube to generate a pedestal current on the target during line flyback. In addition, the pyroelectric camera is able to sense only changes in thermal energy and thus, unlike the conventional vidicon tube, is unable to image steady-state information.
Attempts have been heretofore made to overcome the inability of the pyroelectric camera to sense only dynamic information, commonly by causing movement of the camera or by placing a mechanical chopper in the optical path of the pyroelectric vidicon tube. Such attempts have, however, not proved to be complete successful and have, for example, caused blurring of the readout display, inadequate picture resolution, and/or flickering of the readout display.